AQA GCSE Biology Biology Paper 1 (Higher), June 2023: Question 4
21 marks · Standard Demand difficulty · Extended Answer
Explain the effects of anaerobic respiration, design an investigation into exercise and heart rate, and describe the production and use of monoclonal antibodies to detect anabolic steroids in urine.
Practise this questionQuestion
Question text
04 This question is about exercise.
04.1 During vigorous exercise, anaerobic respiration occurs in a person’s body.
Explain two effects of anaerobic respiration on the person’s body.
[4 marks]
04.2 Design an investigation to show the effect of different types of exercise on the heart
rate of athletes.
[6 marks]
Anabolic steroids are drugs.
Anabolic steroids:
• increase muscle mass in humans
• are banned in most competitive sports.
Some athletes take anabolic steroids to improve their performance in sport.
04.3 Explain how taking anabolic steroids could improve an athlete’s performance.
[2 marks]
Scientists use monoclonal antibodies to test for the presence of anabolic steroids in
an athlete’s urine.
To produce monoclonal antibodies, a mouse lymphocyte is combined with
a tumour cell.
04.4 What type of cell is created when a mouse lymphocyte and a tumour cell combine?
[1 mark]
Tick ( ) one box.
Embryo
Hybridoma
Phagocyte
Stem cell 21
04.5 Describe how scientists make monoclonal antibodies using the cell created when a
mouse lymphocyte and a tumour cell combine.
[3 marks]
04.6 What property makes a monoclonal antibody useful in detecting the presence of an
anabolic steroid in urine?
[1 mark]
Tick ( ) one box.
A monoclonal antibody is quick and easy to produce.
A monoclonal antibody is specific to only one person’s urine.
A monoclonal antibody only binds to the anabolic steroid.
A monoclonal antibody can identify many different drugs at the same time.22
Figure 5 shows a test strip that can detect the presence of an anabolic steroid in an
athlete’s urine.
Figure 5
The end of the test strip is dipped in urine.
The urine moves up through the test strip.
The test area and the control area contain a dye.
The dye turns blue when monoclonal antibodies bind to it.
04.7 Suggest the purpose of the control area in the test strip.
[1 mark]
Figure 6 shows the urine test results of four athletes.
Figure 6
04.8 Describe the evidence in Figure 6 that shows the test for athlete B has not worked.
Suggest one reason why the test did not work.
[2 marks]
Evidence
Reason
04.9 Which athlete has tested positive for anabolic steroids in their urine?
[1 mark]
Tick ( ) one box.
A B C D
Mark scheme
Show the mark scheme
Question 4
AO /
Question Answers Extra information Mark
Spec Ref.
04.1 any two from: mark as pairs 4 AO1
4.4.2.1
• (effect) muscle fatigue or allow muscle cramp
4.4.2.2
oxygen debt occurs (1) ignore fatigue / cramp
unqualified
(reason) caused by (build-up
of) lactic acid (1)
• (effect) (continued) heavy /
deep / fast breathing (1)
(reason) to provide the allow to repay the oxygen debt
oxygen needed to break down
(built-up) lactic acid (1)
• (effect) (continued) increased
heart rate (1)
(reason) to provide the allow to repay the oxygen debt
oxygen needed to break down
(built-up) lactic acid (1)
• (effect) fewer / weaker muscle
contractions (1)
(reason) (because) less do not accept energy being
energy is released / available produced / made / created
(1)
AO /
Question Answers Mark
Spec Ref.
04.2 Level 3: The method would lead to the production of a valid 5-6 AO3
outcome. The key steps are identified and logically sequenced. 4.4.2.2
Level 2: The method would not necessarily lead to a valid 3-4
outcome. Most steps are identified, but the method is not fully
logically sequenced.
Level 1: The method would not lead to a valid outcome. Some 1-2
relevant steps are identified, but links are not made clear.
No relevant content. 0
Indicative content
• test a group of athletes
• use at least two different types / intensities of exercise
• get each athlete to do all exercises or have a large (≥30) group
doing each exercise
• record heart rate for each athlete before and after exercise or
calculate increase in heart rate for each athlete after exercise
• calculate the mean increase in heart rates for each type / intensity
of exercise
• compare mean increase in heart rates for each type / intensity of
exercise
• control variables:
o same (biological) sex or mix of sexes
o same level of activity / exercise
o same age
o same caffeine / drug / medicine intake
o same length of time for exercise
o no health issues / illnesses
o return to resting heart rate before each exercise
AO /
Spec Ref.
04.3 (athlete is) faster / stronger allow description of improved 1 AO2
performance 4.4.2.1
4.4.2.2
allow reference to increased
stamina / endurance
(because more muscle mass so) 1
more / stronger muscle
contractions
AO / 19
Spec Ref.
04.4 hybridoma 1 AO1
4.3.2.1
AO /
Spec Ref.
04.5 any three from: 3 AO1
4.3.2.1
• (cell) is cloned ignore name of cell
• many (identical) cells are allow many clones are produced
produced
• all the cells make the same
antibody
• the antibody is (collected and)
purified
AO /
Spec Ref.
04.6 a monoclonal antibody only binds 1 AO2
to the anabolic steroid 4.3.2.1
AO /
Spec Ref.
04.7 to show that the test is working allow to prevent a false negative 1 AO3
(result) 4.3.2.1
4.3.2.2
ignore to show there are free /
remaining monoclonal
antibodies
AO /
Spec Ref.
04.8 evidence AO3
no blue / visible dye (in control allow no line(s) (in control area) 1 4.3.2.1
area) allow no colour change (in 4.3.2.2
control area)
reason
(because) no (free) monoclonal allow the (free) monoclonal 1
antibodies bound to control area antibodies did not move up the
test strip
20 allow urine did not move up the
or
test strip
(because) there were no (free)
monoclonal antibodies on the
end of the (test) strip
AO /
Spec Ref.
04.9 D 1 AO3
4.3.2.1
4.3.2.2
Total Question 4 21
How to answer it
Exercise Physiology & Monoclonal Antibodies
This question brings together two key biology topics: Bioenergetics (Respiration & Exercise) and Infection & Response (Monoclonal Antibodies).
- Anaerobic respiration: The causes of oxygen debt, lactic acid build-up, and muscle fatigue.
- Required Practical skills: Designing a valid investigation into heart rate changes, identifying key independent, dependent, and control variables.
- Monoclonal antibodies: Production using hybridoma cells, specificity, and interpreting lateral flow test strip results.
Effects of Anaerobic Respiration
Explain two effects of anaerobic respiration on the person's body.
✅ Model Answer (Awarded in Pairs)
Effect 1 & Reason:
- Effect: Muscle fatigue or cramp occurs. [1 mark]
- Reason: Caused by the build-up of lactic acid in muscle tissues. [1 mark]
Effect 2 & Reason:
- Effect: Heavy, deep breathing (or increased heart rate) continues after exercise. [1 mark]
- Reason: To provide extra oxygen to break down lactic acid / repay the oxygen debt. [1 mark]
❌ Common Errors
- "Energy is made/produced": Never say respiration makes or creates energy. State that less energy is released.
- Unlinked answers: Giving two effects without reasons drops 2 marks. The mark scheme links each reason directly to its stated effect.
- Writing just "fatigue" without stating that it affects muscles.
Investigation Design: Exercise Type & Heart Rate
Design an investigation to show the effect of different types of exercise on the heart rate of athletes.
🧠 How to Structure a 6-Mark Method
To reach Level 3 (5–6 marks), your method must be complete, logically sequenced, and yield a valid result. Follow the CORMS/IV-DV-CV layout:
✅ Complete Step-by-Step Method
- Participants: Select a group of athletes (e.g. at least 15–30 healthy individuals) of similar age, fitness levels, and biological sex.
- Independent Variable: Choose at least two distinct types of exercise (e.g. running, cycling, or skipping) performed for the same length of time (e.g. 5 minutes).
- Baseline: Measure and record the resting pulse/heart rate (beats per minute) of each athlete before starting.
- Dependent Variable: Immediately after the exercise ends, measure and record their heart rate again. Calculate the increase in heart rate.
- Recovery & Repeats: Allow athletes to rest completely until heart rate returns to baseline before testing the next exercise type.
- Analysis: Calculate the mean heart rate increase for each exercise type and compare.
💡 Controlled Variables to Mention
- Duration of exercise: Exact same duration (e.g. 5 minutes).
- Intensity / Environment: Same room temperature and intensity where possible.
- Participant state: Same caffeine, medication, or food intake prior to testing; no underlying illnesses.
- Rest interval: Ensuring resting heart rate returns to normal before the next test.
Anabolic Steroids & Performance
Explain how taking anabolic steroids could improve an athlete's performance.
✅ Correct Answer
- The athlete will be faster / stronger / have greater stamina. [1 mark]
- Because: Greater muscle mass allows for more powerful / stronger muscle contractions. [1 mark]
🧠 Exam Tip
Always connect cellular or anatomical changes to physical outcomes: More muscle mass → stronger contractions → athlete runs faster / lifts heavier.
Production & Properties of Monoclonal Antibodies
04.4 Cell Identification [1 mark]
Mouse lymphocyte + Tumour cell = Hybridoma
04.6 Useful Property [1 mark]
A monoclonal antibody only binds to the anabolic steroid.
04.5 How scientists make monoclonal antibodies from the hybridoma [3 marks]
- The hybridoma cell is cloned (divides by mitosis). [1 mark]
- Many identical cells are produced. [1 mark]
- All cells produce and secrete the same specific antibody. [1 mark]
- The antibodies are then collected and purified. [1 mark]
Interpreting Test Strips (Lateral Flow)
04.7 Purpose of the Control Area [1 mark]
To show that the test is working properly (or to prevent a false negative result).
04.8 Athlete B Result Analysis [2 marks]
- Evidence: There is no blue line / no dye visible in the control area. [1 mark]
- Reason: The urine did not move up the strip, OR no free antibodies were bound at the control area / antibodies were missing from the end. [1 mark]
04.9 Positive Test Athlete [1 mark]
Athlete D is the only one who tested positive.
- A: Negative (Control line only).
- B: Invalid (No lines appeared at all).
- C: Invalid (Test line appeared, but no control line to prove test worked).
- D: Positive (Both Test line AND Control line are blue).
Topics
Biology · B3: Infection and Response · B4: Bioenergetics
Question and mark scheme from the AQA GCSE Biology examination, Biology Paper 1 (Higher), June 2023. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.